Characteristics and Evolution of the Composite Petroleum System in Jimsar Depression, Eastern Junggar Basin

There exist three petroleum systems in Jimsar depression of eastern Junggar Basin and its adjacent Bogda piedmont depression. They together shared hydrocarbon pool-forming conditions and formed a composite petroleum system. An analysis of characteristics and evolution of source rocks and petroleum systems suggests that, with fairly good matching of pool-forming conditions, the composite petroleum system is petroliferous. Multi-source and multi-phase hydrocarbon generation and multi-phase pool formation of every petroleum system restrict the critical moments of the composite petroleum system. Having pointed out advantageous hydrocarbon-bearing units, this paper deals with the relationship between the regional tectonic evolution and the formation of the composite petroleum system.